Among target object detection apparatuses, for example, a radar apparatus equipped on a ship generally detects target objects (e.g., other ships and buoys on the sea) by discharging radio waves and receiving reflection waves, and displays the detected target object on a display.
However, when radio waves are discharged from another radar apparatus existing around the radar apparatus of the ship, there is a case where the target object cannot be displayed accurately by the radar apparatus of the ship. This is because, reflection waves from the target object are superimposed on the radio waves from the other radar apparatus, and interference waves appear in the reflection waves. Therefore, the conventional radar apparatuses are configured to remove the interference waves by adding jitter to transmission pulses and scattering the interference waves in a time direction (e.g., JP2009-068896A). Such jitter is determined in advance based on, for example, a PRF (Pulse Repetition Frequency) and a transmission pulse width, which are used in radars.
The RPF and transmission pulse width used in the radars are different depending on the manufacturer and the type of the radar. Therefore, determining an effective pulse transmission method by comparing with all the other radars in advance is extremely difficult. In particular, since fixed radars have significantly larger pulse widths compared to the conventional magnetron radars, influence of interference cannot be completely prevented even by adding jitter in many cases.